It might be worth giving a tool called "devcon" a try - you can make a batch file that will run on suspend or resume to disable / enable hardware and also refresh pci / usb hardware info etc.
I used to use it with an old hauppauge analogue tuner card with good results - on 32bit vista though.
I assume you have tried various versions of drivers for the tuner card, and bios / drivers for the motherboard and graphics / sound card?
I have found that the latest hauppauge drivers are not always the best !
Rob.
Win7, P5Q Pro Turbo, Q6600, GT430, BGT3595, Hauppauge Nova-hd-s2, DM500s, DVBLink.
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